Database common operations

Using System.Collections.Generic;
Using System.Linq;
Using System.Web;
System.Web.UI;
Using System.Web.UI.WebControls;
public partial class _default:system.web.ui.page
{
public void filling ()
{
SqlConnection con = new SqlConnection ();
Con. ConnectionString = "server= (local); uid=sa;pwd=sa;database=stu;";
SqlCommand cmd = new SqlCommand ();
Cmd.commandtext = "SELECT * from student";
Cmd. Connection = con;
SqlDataAdapter SDA = new SqlDataAdapter ();
Sda. SelectCommand = cmd;
Con. Open ();//Opening a database connection
DataSet ds = new DataSet ();
Sda. Fill (ds, "Student");//populate Data set with student table
Con. Close ();//Closing database connection
This. Gridview1.datasource = ds;
This. Gridview1.databind ();
}

Protected void Page_Load (object sender, EventArgs e)
{
this.filling ();
}
protected void Button1_Click (object sender, EventArgs e)
{
SqlConnection con = new SqlConnection ();
Con.c onnectionstring = "server= (local); uid=sa;pwd=;d atabase=stu;";
SqlCommand cmd = new SqlCommand ();
Cmd.commandtext = "INSERT into student values (" + this. TextBox1.Text + "," + this. TextBox2.Text + "," + this. TextBox3.Text + ")";//Add student information
cmd. Connection = con;
Con. Open (); Open the database connection
CMD. ExecuteNonQuery ();//Use ExecuteNonQuery () method to execute the query statement
Con. Close (); Close the connection to the database
}

protected void Button3_Click (object sender, EventArgs e)
{
SqlConnection con = new SqlConnection ();
Con. ConnectionString = "server= (local); uid=sa;pwd=sa;database=stu;";
SqlCommand cmd = new SqlCommand ();
Cmd.commandtext = "Update student set Name= '" + this. TextBox2.Text + "', banji= '" + this. TextBox3.Text + "' where id=" + this. TextBox1.Text + "";
//Modify the corresponding student's information according to the student's number
cmd. Connection = con;
Con. Open ();//Opens the connection to the database
cmd. ExecuteNonQuery ();//Use ExecuteNonQuery () method to execute the query statement
Con. Close ();//Closes the connection to the database

}
protected void button2_click (object sender, EventArgs e)
{
SqlConnection con = new SqlConnection ();
Con. ConnectionString = "server= (local); uid=sa;pwd=sa;database=stu;";
SqlCommand cmd = new SqlCommand ();
Cmd.commandtext = "Delete from student where id=" + this. TextBox1.Text + "";
//delete the corresponding student's information according to the student's number
cmd. Connection = con;
Con. Open ();//Opens Connection
cmd. ExecuteNonQuery ();//Use ExecuteNonQuery () method to execute the query statement
Con. Close ();//Closes connection

}
protected void Button4_Click (object sender, EventArgs e)
{
SqlConnection con = new SqlConnection ();
Con. ConnectionString = "server= (local); uid=sa;pwd=sa;database=stu;";
SqlCommand cmd = new SqlCommand ();
Cmd.commandtext = "SELECT * from student";//Query student table
cmd. Connection = con;
Con. Open ();//Opens the connection to the database
SqlDataAdapter SDA = new SqlDataAdapter ();
Sda. SelectCommand = cmd;
Cmd. ExecuteNonQuery ();//Use the ExecuteNonQuery () method to execute the query statement
DataSet ds = new DataSet ();
Sda. Fill (ds, "Student");//populate data set
Con. Close ();//Closes the database connection
this. Gridview1.datasource = ds;//output to the GridView control in
this. Gridview1.databind ();//Bind data to the GridView control

}
protected void Button5_click (object sender, EventArgs e)
{
SqlConnection con = new SqlConnection ("server= (local); Uid=sa;pwd=sa;database=stu");
Con. Open ();//Opening a connection to a database
if (this. radiobutton1.checked = = True)
{
SqlCommand cmd = new SqlCommand ();
DataSet ds = new DataSet ();
SqlDataAdapter SDA = new SqlDataAdapter ("select * from student where id="
+ this. TextBox1.Text + "", con);
Sda. Fill (ds, "Student");//populate the student table with the data set
This. Gridview1.datasource = ds;
This. Gridview1.databind ();//Bind data to the GridView control
}
if (this. radiobutton2.checked = = True)
{
SqlCommand cmd = new SqlCommand ();
DataSet ds = new DataSet ();
SqlDataAdapter SDA = new SqlDataAdapter ("select * from student where name= '"
+ this. TextBox2.Text + "'", con);
Sda. Fill (ds, "Student");
This. Gridview1.datasource = ds;
This. Gridview1.databind ();//Bind data to the GridView control
}
}

Database common operations